- A
The monitor's HDMI port is defective
Why wrong: The monitor is detected, so the port works; the issue is resolution, not connectivity.
- B
The USB-C cable does not support DisplayPort Alt Mode
Without DisplayPort Alt Mode, the cable cannot transmit the high bandwidth needed for 4K video, limiting resolution.
- C
The laptop's graphics driver is outdated
Why wrong: A driver issue would likely cause no detection or artifacts, not a specific resolution limit.
- D
The monitor's refresh rate is set too high
Why wrong: Refresh rate settings don't prevent a resolution from being selected; the OS typically offers the highest supported resolution.
Question 192 of 1,020
USB-C 4K Monitor Stuck at 1080p: Check DisplayPort Alt Mode
This 220-1201 practice question tests your understanding of display devices. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A user connects a 4K monitor to their laptop using a USB-C port. The monitor is detected, but the resolution is stuck at 1920x1080. The laptop supports 4K output via USB-C. What is the most likely reason?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue:
"most likely"Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
Quick Answer
The answer is that the USB-C cable does not support DisplayPort Alt Mode. This is the most likely reason because while USB-C ports can carry video signals, the cable itself must be specifically rated for DisplayPort Alt Mode or Thunderbolt to handle the high bandwidth required for 4K resolution. A standard USB-C cable designed only for USB 2.0 or lower data rates lacks the necessary lanes for video transmission, so the monitor defaults to 1080p even though the laptop supports 4K output. On the CompTIA A+ Core 1 220-1201 exam, this scenario tests your understanding of how USB-C video capabilities depend on the cable, not just the port—a common trap is assuming any USB-C cable will work for 4K. Remember that not all USB-C cables are created equal; if a 4K monitor is stuck at 1080p, the cable is the first suspect. A handy memory tip: “Alt Mode or Thunderbolt for 4K, or you’ll be stuck in 1080p gray.”
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The USB-C cable does not support DisplayPort Alt Mode
The most likely reason is that the USB-C cable does not support DisplayPort Alt Mode. For a USB-C port to output a 4K video signal, the cable must be capable of carrying DisplayPort signals alongside USB data. If the cable is a standard USB 2.0 or 3.x cable without Alt Mode support, the system will fall back to a lower resolution like 1920×1080, even if the laptop and monitor both support 4K.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The monitor's HDMI port is defective
Why it's wrong here
The monitor is detected, so the port works; the issue is resolution, not connectivity.
- ✓
The USB-C cable does not support DisplayPort Alt Mode
Why this is correct
Without DisplayPort Alt Mode, the cable cannot transmit the high bandwidth needed for 4K video, limiting resolution.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
The laptop's graphics driver is outdated
Why it's wrong here
A driver issue would likely cause no detection or artifacts, not a specific resolution limit.
- ✗
The monitor's refresh rate is set too high
Why it's wrong here
Refresh rate settings don't prevent a resolution from being selected; the OS typically offers the highest supported resolution.
Common exam traps
Common exam trap: answer the scenario, not the keyword
CompTIA often tests the misconception that any USB-C cable can carry video, when in fact only cables explicitly supporting DisplayPort Alt Mode (or Thunderbolt 3/4) can deliver high-resolution video signals.
Detailed technical explanation
How to think about this question
DisplayPort Alt Mode over USB-C uses the SuperSpeed differential pairs (SSTX/SSRX) to carry DisplayPort lanes, while the USB 2.0 pins handle data and power. A cable that lacks Alt Mode wiring will only negotiate USB data, and the system's graphics driver will default to a safe, lower resolution (e.g., 1080p) because it cannot establish a DisplayPort link. In real-world scenarios, users often grab a cheap charging cable that works for power but fails for video, leading to this exact symptom.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A practitioner preparing for the 220-1201 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Display Devices — study guide chapter
Learn the concepts, then practise the questions
- →
Display Devices practice questions
Targeted practice on this topic area only
- →
All 220-1201 questions
1,020 questions across all exam domains
- →
CompTIA A+ Core 1 220-1201 study guide
Full concept coverage aligned to exam objectives
- →
220-1201 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related 220-1201 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Mobile Device Hardware Servicing practice questions
Practise 220-1201 questions linked to Mobile Device Hardware Servicing.
Mobile Device Connection Methods practice questions
Practise 220-1201 questions linked to Mobile Device Connection Methods.
Mobile Device Accessories practice questions
Practise 220-1201 questions linked to Mobile Device Accessories.
Mobile Device Network Connectivity practice questions
Practise 220-1201 questions linked to Mobile Device Network Connectivity.
Mobile Device Application Support practice questions
Practise 220-1201 questions linked to Mobile Device Application Support.
Network Protocols practice questions
Practise 220-1201 questions linked to Network Protocols.
TCP & UDP Ports practice questions
Practise 220-1201 questions linked to TCP & UDP Ports.
Wireless Networking Technologies practice questions
Practise 220-1201 questions linked to Wireless Networking Technologies.
Network Services practice questions
Practise 220-1201 questions linked to Network Services.
Network Configuration Concepts practice questions
Practise 220-1201 questions linked to Network Configuration Concepts.
Common Networking Hardware practice questions
Practise 220-1201 questions linked to Common Networking Hardware.
IP Addressing practice questions
Practise 220-1201 questions linked to IP Addressing.
Practice this exam
Start a free 220-1201 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this 220-1201 question test?
Display Devices — This question tests Display Devices — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The USB-C cable does not support DisplayPort Alt Mode — The most likely reason is that the USB-C cable does not support DisplayPort Alt Mode. For a USB-C port to output a 4K video signal, the cable must be capable of carrying DisplayPort signals alongside USB data. If the cable is a standard USB 2.0 or 3.x cable without Alt Mode support, the system will fall back to a lower resolution like 1920×1080, even if the laptop and monitor both support 4K.
What should I do if I get this 220-1201 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Keep practising
More 220-1201 practice questions
- During a network cable installation, a technician needs to verify that a newly run Cat6 cable is properly terminated and…
- A technician is troubleshooting a laptop that will not charge. The battery is removable, and the power adapter works on…
- A customer brings in a smartphone with a broken charging port. They want the port replaced. During disassembly, the tech…
- A user reports that their laptop's keyboard types random characters when certain keys are pressed. The laptop has not be…
- A technician is troubleshooting a laptop that shuts down randomly after a few minutes of use. The fan is spinning, and t…
- A user reports that their laptop battery no longer charges and the system only runs when plugged in. You test the AC ada…
Last reviewed: Jul 4, 2026
This 220-1201 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 220-1201 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.